Getting a Green dragon out of a lake of acid

Okay, Here's the situation. We're a very low level party of monsters. We were doing a favor for some Nixies in getting rid of a green dragon that is polluting a river. We got to where the green dragon was living and I gave it a serious beating. It retreated into the water, which the DM has ruled is just a big vat of acid now, really. It's sitting at the bottom of this pool. The pool is in a cavern with a waterfall at the cave entrance. The water from the waterfall is clean water, but the pool is highly concentrated breath weapon. The waterfall sploshes water in and stirs it up and send it down the river.

We know from the DM that it is a 30ft deep pool of water, 50 feet radius. We know that, if we can somehow damn or divert the river above, the waterfall will cease and 10ft of the water in the pool will skim off down the bottom part of the river, drying out. The dragon is seriously hurt and will not come out willingly. We're not sure how to deal with it if we go ahead and block off the fresh water. We can't destroy the area, since it is the Nixies home and they'd be pissed.

Opponent: Green Dragon Wyrmling in a pool of acid.

Group:
Fire Elemental 1/Barbarian 1
Holyphant 2/Cleric 1
Lilliend 2/Bard 1
Hobgoblin Rogue 2
Half-Ogre/Half Dwarf 1/Druid 1/Ranger 1

We're obviously all monsters. Everyone but the hobgoblin is still working on their monster class (savage species). The Fire Elemental (me) has an aversion to water, but this isn't water. It'll still freak him out. Some of the ideas the group has revolves around boiling the acid by tossing me in the lake (or sticking me on a shield in the lake or some other heat conductive metal). We've got 270 gold to our name and a week before the next game to figure this out.

We can use the PHB, DMG, FRCS (3.0), & Magic of Faerun (3.0). The game itself is v3.5 (though we're using 3.0 Faerun books, so the DM calls it v3.25).

So, can anyone help us solve this? We're kinda stumped.

Boiling the acid via heat-conductive metal sounds good. But, of course, some acids have higher boiling points than water, and your DM might decide that this is one of them. Of course, if he's going to be this much of a stickler for chemistry, point out that green dragons can breathe water, not acid.

The best option, barring that, would probably be getting the dragon to the surface, then sniping it with ranged attacks. Does the rogue have any ranks in Use Magic Device? If he does, buy a scroll of some illusion to either lure the dragon to the surface or chase it there (such as a larger dragon). From your description, it's in dire enough straits that all you need is a round or two.

Or, you could use Summon Monster I in order to summon a celestial porpoise. They have acid resistance 5 (good if it's a weak acid) and a faster swim speed than a green dragon, so you could use it to flush the wyrmling out.

Demiurge out.

The rogue is built around being extremely sneaky. His weapon of choice is his great bow. Don't think he has any UMD. The cleric could take Summon Monster 1 tomorrow, though, I believe. It'll only last for 6 seconds, but that's enough to attack once. Might tick the dragon off.

Good ideas. Anyone have others?

I don't know much of chemistry so correct me if I'm wrong, but wouldn't that much water dilute the acid from the breathe weapon of the wyrmling dragon?

Unless the dragon used its breath weapon continuously in order to keep the water acidic, and there was no outlet for the water to go, probably. Oh well, suspension of disbelief and all that.

Demiurge out.

What's in it for your group? I mean, what are the Nixies going to give you for doing them this favour?

Seeing as how your group are all monsters (and a hobgoblin and half ogre, too) it wouldn't seem too strange to add a sixth monster to your merry little band.

Seriously, I'd join forces with the dragon and wreak havoc upon the Nixies. Nixies can't be trusted anyhow, and wouldn't it be cool to have a dragon in your party?

Reasoning given was the dragon has been there for several months. While thetop ten feet do get mixed around, the bottom 20 are fairly stagnant. So, the further down you go, it gets much more concentrated.

The water being effectively acid helps us in the way that my character can actually enter it. If it were just water, he'd be out of the fight (whole water aversion thing). Of course, we'd have to get him protected vs the acid, which is not something we can do at present level.

Town itself is several days away and is not of adaquet size for magical item purchase. If we leave, we don't know what exactly the dragon will go. We've gotten the distinct feeling that letting it go free is not a good thing. It has already polluted a water supply , killed lots of vegetation, and eaten the wildlife population of the surrounding area. And it's just a baby.

We're mostly goods. I don't know everyone's alignment, but I believe we have 2 Neutral Goods (bard & druid), 2 Chaotic Goods (barbarian & cleric), and the hobgoblin is lawful pragmatic, as he says (lawful neutral and not quite evil).

I missed the session with the Nixies, so I don't know for sure. I believe that they need the Nixies as character references or something (Guedo, want to fill us in on this?)

I don't think any of us or the DM wants to team up with the dragon. From my impression tonight, the group seemed to actually like the Nixies.

It's at the bottom of a waterfall? Drop big rocks and heavy spears on it. Limestone would take care of the acid if it became necessary to.

It's at the bottom of a waterfall? Drop big rocks and heavy spears on it. Depending on how hot fire elementals get, there's always molten metal/rock too. Limestone would take care of the acid if it became necessary to.